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Factors affecting hatching success of golden apple snail eggs: Effects of water immersion and cannibalism
Abstract and Figures
The golden apple snail (Pomacea maculata Perry) is an invasive species that lays its eggs out of water but is otherwise aquatic. To investigate this behavior and
potential management techniques, we conducted experiments to examine the physical effects of immersion and underwater egg
predation on hatching success. Predation on submerged eggs by P. maculata adults reduced hatching success by ∼99%. In predator-free conditions, hatching success was reduced 75% by immersion in water
and was negatively correlated with time submerged. Our results suggest that both underwater egg predation and low immersion
tolerance may be exploited to limit the spread of P. maculata.
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... Apple snails are voracious eaters (Boland et al., 2008;Wong et al., 2010), preying on animal tissue including eggs and juveniles of other snails, as well as on macrophytes or detritus (Wood et al., 2006;Kwong, Chan & Qiu, 2009;Karraker & Dudgeon, 2014;Saveanu, Manara & Martin, 2017;Carter, Johnson & Merino, 2018). Indeed, some apple snails, such as P. maculata (Horn et al., 2008) or A. platae (Tiecher et al., 2014), even consume egg masses of their own species. As a consequence of such cannibalism, experiments with egg masses of P. maculata have shown that egg masses kept under water were consumed almost entirely by conspecifics, and to an extent that hatching success was reduced to c. 1% (Horn et al., 2008). ...
... Indeed, some apple snails, such as P. maculata (Horn et al., 2008) or A. platae (Tiecher et al., 2014), even consume egg masses of their own species. As a consequence of such cannibalism, experiments with egg masses of P. maculata have shown that egg masses kept under water were consumed almost entirely by conspecifics, and to an extent that hatching success was reduced to c. 1% (Horn et al., 2008). The predation of egg masses by apple snails is clearly not accidental (Tiecher et al., 2014), supporting the hypothesis that predation of egg masses by ampullariid gastropods and other predators represents a significant evolutionary pressure favouring oviposition above the water line (Turner, 1998). ...
The ability to use oxygen from both air and water has been considered key to the colonization of terrestrial environments by invertebrates. The freshwater gastropod Pomacea figulina generally lives submerged, although females lay their eggs mainly above water during nighttime, on the stems of aquatic plants, and the embryos develop inside the air-exposed calcareous egg capsules. However, little is known about the physiological adaptations that the ovipositing females and the developing embryos have developed to breathe in air. In this study, we report sexual differences in the aerial and aquatic oxygen consumption of adults and embryonic respiration in aerially developing egg clusters. We found that the males and females of this species can obtain oxygen from both water and air, although uptake rates for both sexes were much lower in air than in water. Females in air consumed oxygen 42% faster than males, which may be related with the habit of egg laying above water level. Developing embryos inside calcareous eggs obtained oxygen faster when submersed under water than when exposed to air, although embryos near hatching were better able to use oxygen from both air and water than embryos at earlier stages of development. Our data suggest that for P. figulina, laying eggs in the terrestrial environment may be more a strategy for protecting embryos from predators than a respiratory adaptation.
... To manage and curb further spread especially to other risk areas, the following containment measures are proposed: (1) undertake training and awareness regarding P. canaliculata through the relevant national and regional or international organisations; (2) prevent field entry by snails, using field screens as physical barriers especially into the uninfested sections; (3) practice physical/ mechanical control through hand picking of snails and crushing eggs and/or knocking eggs into the water; (4) community-based snail management through synchronised farm activities like land preparation, irrigation and application of control measures (an area-wide management approach); (5) introduce changes to the cropping system by avoiding ratoon crops to limit resource availability for P. canaliculata; (6) practice cultural practices like alternate wetting and drying (AWD) of paddies and creating shallow hollows in paddies to form small ponds where snails gather, aiding efficient collection and disposal; (7) change planting patterns by encouraging transplanted rice over direct seeding, as seedlings are especially vulnerable to apple snail herbivory; (8) manage water in paddies by limiting water levels to less than 2 cm above the soil surface to reduce P. canaliculata movement and dispersal; (9) desilting of canals to minimize the habitable areas where the snails lay their eggs and reduce their populations; among other practices Horn et al. 2008;Wada 2004). ...
The invasive apple snail Pomacea canaliculata has become a significant concern in invaded habitats beyond its native range. It was reported in Kenya in 2020 invading one of the largest rice-producing schemes, the Mwea irrigation scheme. Delimiting surveys were conducted across five key rice-producing schemes (Mwea, Bura, Hola, Ahero and West Kano) in Kenya to establish the extent of the invasion and develop effective quarantine and management strategies within the Mwea scheme and other risk areas. Additionally, the ensemble model approach was used to model the potential distribution of P. canaliculata in Eastern Africa (as defined by the United Nations Geoscheme). Over 80% of the Mwea scheme was infested with P. canaliculata , an expansion from the initial infestation point (Ndekia). The mean number of adults/m ² and egg clutches/m ² were 8.4 ± 0.9 (SEM) and 7.7 ± 1.4 (SEM), respectively, with varying densities across sections. No adults or eggs of P. canaliculata were found in the four schemes outside the Mwea scheme. The model predicted high suitability for P. canaliculata in the southwest of Kenya,and in coastal areas, with all surveyed areas marked as highly suitable. . Regionally, high-risk areas include Malawi, Madagascar, and Uganda. Mozambique, Tanzania, and Ethiopia showed localised areas of high suitability. Conversely, Sudan, South Sudan, Eritrea, Djibouti and Somalia were largely unsuitable for P. canaliculata . Given the potential for further spread, strict quarantine measures are essential to prevent the spread of P. canaliculata in Kenya and its introduction to uninvaded regions of Eastern Africa. Alongside this, implementing IPM e strategies is crucial for effective pest management and the protection of agricultural ecosystems.
... The effects of water stress on various Pomacea sp. have shown a reduction in hatching rates in submerged clutches [2,11,12]. The physiological stress provoked by submersion may be related to oxygen availability, solute losses, pH changes or osmotic pressure [2].Exposure to water stress minimally decreased hatching success of P. maculata clutches during this study. ...
... The application of electric shock with 0.35 A/m 2 or more can inactivate GAS and hence cease their reproduction process (Yagyu et al., 2005). The water level could also manipulate as prolonged water immersion period resulted in the reduction of GAS egg's hatching up to 75% (Horn et al., 2008). ...
Golden apple snails (GAS) (Pomacea spp.) is one of the major pests that rampantly invaded many countries and brought a heavy bloom to agricultural cultivation. Their invasion had resulted in huge crop damage and ultimately caused massive economic loss. For the past few decades, many strategies had been developed to overcome the GAS infestation. Among all the strategies, chemical synthetic molluscicides had been the mainstay within the farmer community. Despite their effectiveness in controlling the GAS infestation, extensive use of chemical molluscicides has negative impacts on humans, non-targeted organisms, and the environment. Climate change is expected to hasten the reproduction of GAS, necessitating the development of more sustainable GAS mitigation strategies. This paper examines the current stage of GAS invasion and its implications for global rice production. This review also includes an in-depth discussion of the various potential biological based strategies involved in pest management, and the recent technological breakthroughs in entomopathogenic nematodes and entomopathogenic fungi as molluscicides, integrated pest management, and precision pest management. To summarize, this review provides a potential trend in the use of biocontrol as a substitute for chemically manufactured synthetic molluscicides for the sustainable management of GAS.
... The Golden Apple Snail Pomacea canaliculata (Lamark, 1822), native to South America, is an invasive freshwater gastropod (Low and Anderson 2017). The snails were introduced to Asia as a high-protein food and as an aquarium pet, but they were released into the wild after complete commercial failure (Horn et al. 2008). Golden Apple Snails quickly established populations in natural and artificial aquatic systems because of their high reproductive ability, fast growth rate, and ability to search for temporary shelters (Andre 1964), but also, importantly, because of their strong adaptability to temperature changes, drought, and water pollution , Mack et al. 2000, Carlsson 2006, Joshi 2007, Wada and Matsukura 2011, Martin et al. 2012. ...
... According to Henley et al. (2000), increased turbidity and sedimentation can reduce dissolved oxygen in the water column. This effect may contribute to hatching failure due to a reduction in oxygen availability for developing embryos, and thereby preventing proper embryonic development (Horn et al., 2008). Moreover, suspended particles may coat the surfaces of eggs, which reduces the flushing of metabolic wastes generated by the eggs (Bash et al., 2001). ...
Marine gastropod eggs are often distributed in the intertidal zone, where they are potentially exposed to short-term salinity and turbidity changes due to heavy rains that may adversely affect their embryonic development. In this study, the embryos of two abalone species, disk abalone Haliotis discus discus and giant abalone Haliotis gigantea, were exposed to various salinities (34, 30, 26, 22, 18 and 14 psu) or turbidities (0, 100, 300, 500 and 700 NTU) for a single 3 h period, and subsequently maintained at normal control conditions (34 psu and 0 NTU). The short-term low salinity stress decreased the hatching and survival rates, and increased the abnormality rate for both species. As for turbidity stress, negative effects on hatching and survival rates were observed in both species when their embryos were exposed to increased turbidity. The abnormality rates of both species at turbidities of 500 and 700 NTU were significantly higher than those at turbidities of 0 and 100 NTU. Overall, exposure of embryos to low salinity or high turbidity for even a short period can clearly have substantial impacts on the embryonic development of the two abalone species, and disk abalone was more sensitive to salinity and turbidity stresses compared to giant abalone.
... Vale ressaltar que algumas desovas foram postas fora da lagoa, representando 4% A postura de ovos acima do nível da água é uma característica da maioria das espécies de Pomacea (SNY-DER; SNYDER, 1971). Em áreas que sofrem mudanças sazonais, o nível da água pode subir acima da altura da desova na incubação, ficando vulnerável aos predadores aquáticos e aos efeitos negativos da própria água, como o estresse hídrico, que pode afetar a integridade estrutural das massas de ovos, reduzindo o desenvolvimento embrionário (TURNER, 1998;HORN et al., 2008). Em um estudo com Pomacea insularum (D'Orbigny, 1839), Burks, Kyle e Trawick (2010), en-contraram desovas submersas que mesmo em proporções baixas, representaram a causa mais frequente de mortalidade dos ovos. ...
A seleção do ambiente para desova é uma tarefa importante para os organismos, uma vez que estabelece as condições de sobrevivência e desenvolvimento dos ovos. Gastrópodes do gênero Pomacea são encontrados em ambientes límnicos e apresentam uma alta diversidade em regiões tropicais e subtropicais. Esses organismos depositam uma massa sólida de ovos acima do nível da água em substratos variados. Sendo assim, objetivou-se, nesse trabalho, avaliar a preferência por sítios de oviposição de Pomacea spp. na Área de Proteção Ambiental da Lagoa de Jijoca, no Ceará. Em campo foram determinadas medidas de profundidade, distância para o nível da água, distância para a margem da lagoa, quando as desovas eram depositadas fora da água, tamanho, número de ovos por desova e substratos escolhidos. No total foram encontradas 347 desovas nos seis pontos amostrados, a maioria ocorreu entre 11 e 32 cm de altura e apresentaram distâncias variáveis para o nível da água. Desovas de menor tamanho foram predominantes, mas a contagem do número de ovos por desovas revelou um alto número de ovos, mesmo em pequenas desovas. O substrato preferencial para oviposição foi Borreria verticillata. Sugere-se que o comportamento de escolha do sítio de oviposição de espécies do gênero Pomacea é adaptativo, variando de acordo com o meio e as condições em que estão inseridas.
... Factors that regulate the egg hatchability have been exploited by researchers in order to control the spread of invasion at early life stage. Horn et al. (2008) found that an immersion of eggs in water has reduced the hatching success by more than 75%. Hatchability of eggs was affected upon exposure to chemicals such as extract of Barringtonia racemose (Musman et al., 2013) and apple wax (Der-Chung et al., 2005). ...
The Golden Apple Snail (GAS), Pomacea canaliculata is an invasive species that has become a serious pest organism in rice fields in Southeast Asia since 1980s. This study was conducted to assess the hatchability of eggs under a combination effect of temperature and light. The clusters of eggs were exposed to different temperature (28 o C, 30 o C, 32 o C, 34 o C and 36 o C) and under the presence and the absence of light. The finding showed that the cluster of egg hatched faster with an increase of temperature (2-way ANOVA; P < 0.05). However, the egg hatchability was not impacted by the presence or the absence of light. The combined effect between temperature and light on egg hatchability was also insignificant (2-way ANOVA; P > 0.05). Our findings indicate that temperature alone produces the main impact on the egg hatchability. Therefore, this knowledge provides an initial understanding to predict the population dynamic and geographical distribution of Pomacea from Malaysia particularly in the effort to hamper their ecological invasion.
This datasheet on Pomacea maculata covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Vectors & Intermediate Hosts, Diagnosis, Biology & Ecology, Environmental Requirements, Natural Enemies, Impacts, Uses, Prevention/Control, Further Information.
05, 0.10, 0.20, 0.30 และ 0.40 mg/L พบว่ าที ่ ความเข้ มข้ น 0.40 mg/L มี อั ตราการเพาะฟั กต ่ าที ่ สุ ด (39.61%) และทุ กความเข้ มข้ น มี อั ตราเพาะฟั กน้ อยกว่ ากลุ ่ มควบคุ มอย่ างมี นั ยส าคั ญทางสถิ ติ (p<0.05) ความผิ ดปกติ ที ่ ตรวจสอบได้ เมื ่ อไข่ ได้ รั บสั มผั สกั บแคดเมี ยมคลอไรด์ พบว่ าที ่ ความเข้ มข้ นของแคดเมี ยม 0.40 mg/L มี ลั กษณะของเซลล์ ไข่ ผิ ดปกติ มากที ่ สุ ด (61.12%) และเกิ ดความผิ ดปกติ ของตั วอ่ อนมากที ่ สุ ดเช่ นกั น (63.83%) ยิ ่ งไปกว่ านั ้นเมื ่ อน าหอยเชอรี ่ ขนาดกลางมาทดสอบถึ งค่ าความเป็ นพิ ษของแคดเมี ยมคลอไรด์ ที ่ ก่ อให้ เกิ ดการตาย 50% ที ่ เวลา 96 ชั ่ วโมง พบว่ ามี ค่ าประมาณ 1.25 (7.143-2.234) mg/L เมื ่ อตรวจสอบรู ปแบบของอะซิ ทิ ลโคลี นเอสเทอเรส พบว่ ามี 1 isoform ที ่ มี ขนาด 71 kDa เมื ่ อ ศึ กษาโดยใช้ เทคนิ ค SDS-PAGE การแสดงออกของอะซิ ทิ ลโคลี นเอสเทอเรส พบว่ าจะลดลงตามระดั บความเข้ มข้ นที ่ หอยเชอรี ่ ได้ รั บสั มผั สแคดเมี ยม คลอไรด์ ในระดั บความเข้ มข้ นที ่ ไม่ ก่ อให้ เกิ ดการตาย คื อ 0, 0.05, 0.10, 0.20, 0.30 และ 0.40 mg/L เมื ่ อได้ รั บสั มผั สสารเป็ นเวลา 96 ชั ่ วโมง ขี ดจ ากั ดการตรวจสอบ คื อ 0.156, 0.312, 0.625, 2.5 และ 5 µg/µl ส่ วนในระดั บที ่ ก่ อให้ เกิ ดการตาย คื อ ระดั บความเข้ มข้ น 0, 0.50, 1.00, 1.50, 2.0 และ 2.50 mg/L ขี ดจ ากั ดของการตรวจสอบโดยใช้ เทคนิ คดอทบลอท คื อ 10, 10, 10, 10, 10 , 20 µg/µl ค าส าคั ญ : แคดเมี ยมคลอไรด์ ; ตั วชี ้วั ดทางชี วภาพ ; หอยเชอรี ่ ; อะซิ ทิ ลโคลี นเอสเทอเรส
Aspects of predation on the apple snail, Pomacea canaliculata, an important pest of rice, by the Norway rat, Rattus norvegicus, were studied near a drainage canal in southern Japan. Most of the shells attacked by the rats were broken in a characteristic way, from the outer edge of the last whorl up to the attachment site of the columellar muscle. The rats ate all the flesh of the snails except for the albumen gland of the female. They preferred Pomacea canaliculata to another freshwater snail Semisulcospira libertina. They preferred large Pomacea snails to small ones but showed no preference between the sexes of the snails. The numbers of snails attacked within 12 hours varied from 0-12 per rat hole, and predation was almost always nocturnal.
This study investigated the potential of ducks for the control of the golden apple snail in irrigated rice. The varieties of duck recommended for the biological control of snail in decreasing preference were William Siam > Taiwan > Mallard > Peking > Muscovy. Cherry Valley, a variety with a bigger body size was not suitable for snail control because of its poor adaptation to rice field conditions. A density of 5–10 ducks ha−1 in continuous grazing for a period of 1–2 months significantly reduced the pest density from 5 snailsm−2 to less than 1 snail m−2. This density of ducks was recommended for biological control of snails in rice. Timely release of ducks was crucial as they damaged young rice seedlings. In transplanted rice, it was appropriate to release the ducks when the seedlings were 4 weeks old. For direct seeded rice, a longer waiting period of 6 weeks was necessary. Numerically, ducks preyed on more snails in transplanted than in direct seeded rice, but the difference was not statistically significant. The increase in plant density under direct seeding probably reduced the browsing efficiency of the ducks. This difference would be expected to diminish under prolonged grazing. It is suggested that ducks were an effective biological control agent against the golden apple snail.
A stock population of the apple snail has been maintained for artificial selection without human interference and has become inbred. Hatchability fluctuated significantly among the egg lumps, and average hatchability decreased with the decrease in number of mature snails in the stock population.
Heritability of hatchability was estimated from the regression line of hatchabilities of offspring to that of their parents; the value was 0.461. The realized heritability was calculated from the first selection for high and low hatchability, and the values were 0.398 for high hatchability and 1.427 for low hatchability.
High heritability probably involved heterotic effects, because of decreased hatchability observed in full-sib mating.
Pomacea canaliculata is a neotropical freshwater snail that has invaded many countries around the world, becoming a serious pest of rice and a menace to native snails. In southern Pampas (Argentina) from late spring to early fall females deposit aerial clutches composed of hundreds of calcareous eggs on emergent substrates. Local bodies of water frequently undergo fluctuations in water level, resulting in extensive submersion of clutches or dropping of hatchlings out of water. The effects of aerial exposure on hatchlings and of submersion on development were analyzed experimentally. The submersion of the egg masses of P. canaliculata increased the duration of development up to approximately 50% and caused a decrease of up to 32% in hatching rate. The calcareous capsule, large size, and dense packaging of eggs probably impede an adequate oxygen supply to embryos when submersed or may interfere with the hatching mechanism. The embryos were unable to develop completely and to hatch under water. Submersion frequently caused the disintegration of newly laid clutches and the premature hatching of eggs in late stages of development, resulting in hatchlings with underdeveloped bodies. Aerial exposure of hatchlings, under conditions similar to those occurring in the field in midsummer, killed 99% after only four days, irrespective of the presence or absence of moist soil. During droughts of several consecutive years recruitment could be seriously affected.